The play involves only two nameless characters, designated “White” and “Black”, their respective skin colors. Offstage, just before the play begins, Black saves White from throwing himself in front of a train, the Sunset Limited. All of the action takes place in Black’s spare apartment in urban New York, where the characters go (at the behest of Black) after their encounter on the platform. Black is an ex-convict and an evangelical Christian. White is an atheist and a professor. They debate the meaning of human suffering, the existence of God, and the propriety of White’s attempted suicide.